Diagnostic Accuracy of Stroke Volume Variation (SVV) vs Pleth Variability Index (PVI) for Predicting Fluid Responsiveness in Laparoscopic Major Abdominal Surgery-A Prospective, Paired, Cohort Study
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 300
- 试验地点
- 3
- 主要终点
- Area under the ROC curve (AUROC) of stroke volume variation (SVV) and Pleth Variability Index (PVI) for predicting fluid responsiveness to a 250-mL crystalloid bolus
研究概览
简要总结
This study will compare two operating-room monitors-stroke volume variation (SVV, from the arterial line) and the Pleth Variability Index (PVI, from the pulse oximeter)-to see which one more accurately predicts whether giving a small fluid bolus will improve the heart's pumping during laparoscopic major abdominal surgery. Adults having elective surgery under general anesthesia will receive two small, timed 250-mL crystalloid infusions as part of routine care (one before and one after creation of the pneumoperitoneum). The research team will record SVV and PVI values just before and three minutes after each infusion while keeping these readings hidden from the clinicians so that usual care is not changed. No experimental drugs or devices are used. The main goal is to learn which index better identifies "fluid responsiveness," so future care can be safer and more consistent. Potential risks are minimal and relate to the small fluid boluses (temporary changes in blood pressure or heart rate); the test stops if the anesthesiologist has any safety concerns. There is no direct benefit to participants, but results may help guide fluid therapy for similar patients in the future. The study is being conducted at a single academic hospital in the Republic of Korea and plans to enroll about 300 adults.
详细描述
Background and rationale. Goal-directed fluid therapy during laparoscopic major abdominal surgery remains variable because dynamic preload indices perform inconsistently under pneumoperitoneum and positional changes. Stroke Volume Variation (SVV, derived from the arterial pressure waveform) and the Pleth Variability Index (PVI, derived from the pulse oximeter) are both widely available and non-drug, non-investigational monitors. A head-to-head, paired accuracy study using standardized fluid challenges can clarify which index better identifies fluid responsiveness in this setting.
Objectives. Primary: Compare the diagnostic accuracy (area under the ROC curve, AUROC) of SVV vs PVI for predicting fluid responsiveness to a small crystalloid bolus during laparoscopic major abdominal surgery.
Key secondary objectives: (1) determine optimal decision thresholds and report sensitivity, specificity, predictive values, and likelihood ratios; (2) compare calibration and classification performance (Youden index, net reclassification); (3) assess effect modification by pneumoperitoneum status, body mass index, ventilation parameters, and vasoactive use; (4) describe peri-bolus hemodynamic changes.
Design and setting. Prospective, single-center, paired diagnostic-accuracy cohort. Adults undergoing elective laparoscopic major abdominal surgery under general anesthesia are enrolled. Each participant undergoes up to two standardized 250-mL crystalloid fluid challenges delivered over ~3 minutes at two time points when feasible: (A) before insufflation and (B) after establishment of pneumoperitoneum at a hemodynamic steady state. Because both indices are recorded around the same fluid challenges, each participant serves as his/her own control.
Index tests. SVV (from the arterial pressure monitor) and PVI (from the pulse-oximetry monitor) are captured immediately before ("pre-bolus") and at ~3 minutes after each bolus. Index values are recorded by trained research staff and kept masked from anesthesia clinicians to avoid influencing usual care.
研究设计
- 研究类型
- Observational
- 观察模型
- Cohort
- 时间视角
- Prospective
入排标准
- 年龄范围
- 19 Years 至 —（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Age ≥18 years
- •ASA physical status I-III
- •Elective laparoscopic major abdominal surgery under general anesthesia
- •Arterial line in place for clinical care
- •Able to provide informed consent
- •Arterial and plethysmographic waveforms adequate for measurement
排除标准
- •linically significant arrhythmia (e.g., atrial fibrillation with irregular R-R)
- •Severe valvular heart disease or intracardiac shunt
- •Pregnancy
- •Severe right-heart failure or condition where a fluid bolus is unsafe
- •Ongoing hemodynamic instability requiring rapid vasoactive titration at assessment
- •Persistently unreliable arterial/pleth signals despite optimization
- •Any situation the anesthesiologist judges that the fluid challenge is unsafe
研究组 & 干预措施
Laparoscopic Surgery Cohort
Adults undergoing elective laparoscopic major abdominal surgery under general anesthesia at a single academic hospital. Each participant may receive up to two standardized 250-mL crystalloid fluid challenges (pre- and post-pneumoperitoneum). SVV and PVI are recorded around each bolus; no assignment or experimental treatment.
干预措施: Pleth Variability Index (PVI) monitoring (Device)
Laparoscopic Surgery Cohort
Adults undergoing elective laparoscopic major abdominal surgery under general anesthesia at a single academic hospital. Each participant may receive up to two standardized 250-mL crystalloid fluid challenges (pre- and post-pneumoperitoneum). SVV and PVI are recorded around each bolus; no assignment or experimental treatment.
干预措施: Stroke Volume Variation (SVV) monitoring (Device)
结局指标
主要结局
Area under the ROC curve (AUROC) of stroke volume variation (SVV) and Pleth Variability Index (PVI) for predicting fluid responsiveness to a 250-mL crystalloid bolus
时间窗: Intraoperative: from the pre-bolus baseline to ~3 minutes after each standardized 250-mL crystalloid bolus (up to two episodes per participant: before and after pneumoperitoneum).
Index tests: pre-bolus SVV (arterial waveform-derived) and PVI (pulse-oximetry-derived). Reference standard: fluid responsiveness defined as a \>=10% increase in stroke volume index measured about 3 minutes after the 250-mL crystalloid bolus using arterial pulse contour analysis. ROC curves will be built for SVV and PVI to discriminate responders vs non-responders; AUROCs will be compared with a paired DeLong test with patient-level clustering. Unit: AUROC (0-1; higher indicates better discrimination).
次要结局
- Sensitivity of prespecified SVV thresholds for predicting fluid responsiveness(Intraoperative: pre-bolus baseline to about 3 minutes after each 250 mL bolus (up to two boluses).)
- Specificity of prespecified SVV thresholds for predicting fluid responsiveness(Intraoperative: pre bolus baseline to about 3 minutes after each 250 mL bolus (up to two episodes per participant).)
- Sensitivity of prespecified PVI threshold for predicting fluid responsiveness(Intraoperative: pre bolus baseline to about 3 minutes after each 250 mL bolus (up to two episodes per participant).)
- Specificity of prespecified PVI threshold for predicting fluid responsiveness(Intraoperative: pre bolus baseline to about 3 minutes after each 250 mL bolus (up to two episodes per participant).)
- Optimal cutoffs for SVV using Youden index(Intraoperative: pre bolus to about 3 minutes post bolus.)
- Optimal cutoffs for PVI using Youden index(Intraoperative: pre bolus to about 3 minutes post bolus.)
- Percent change in stroke volume index after a fluid bolus(Intraoperative: pre bolus baseline to about 3 minutes after each 250 mL bolus.)
- Change in mean arterial pressure after fluid challenge(Intraoperative: pre bolus to about 3 minutes post bolus.)
- Change in heart rate after fluid challenge(Intraoperative: pre bolus to about 3 minutes post bolus.)
- Incidence of any predefined hemodynamic adverse event within 10 minutes of a study bolus(From bolus start to 10 minutes after each bolus during surgery.)
研究者
Cheol Lee,MD,PhD,
Professor
Wonkwang University Hospital